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    <title>Document</title>
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    <script>
      //需求：求6！=
      function fact(n) {
        if (n == 1) {
          return 1;
        } else {
          //return n * fact(n - 1);
          return n * arguments.callee(n - 1);
        }
      }
      console.log(fact(6));

      //需求：求1！+2!+3!+......+6!=  递归调用
      var sum = 0;
      for (var i = 1; i <= 6; i++) {
        sum += fact(i);
      }
      console.log(sum);
    </script>
  </body>
</html>
